=========================
==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:648 [inline]
BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:730
Read of size 1 at addr ffff888109fed193 by task udevd/2861

CPU: 0 UID: 0 PID: 2861 Comm: udevd Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
 string_nocheck lib/vsprintf.c:648 [inline]
 string+0x471/0x4d0 lib/vsprintf.c:730
 vsnprintf+0x422/0x1300 lib/vsprintf.c:2949
 add_uevent_var+0x183/0x3a0 lib/kobject_uevent.c:682
 input_dev_uevent+0x162/0x910 drivers/input/input.c:1737
 dev_uevent+0x2f1/0x870 drivers/base/core.c:2783
 uevent_show+0x1ca/0x3a0 drivers/base/core.c:2830
 dev_attr_show+0x52/0xa0 drivers/base/core.c:2491
 sysfs_kf_seq_show+0x217/0x3f0 fs/sysfs/file.c:65
 seq_read_iter+0x32f/0x1270 fs/seq_file.c:231
 kernfs_fop_read_iter+0x46c/0x610 fs/kernfs/file.c:290
 new_sync_read fs/read_write.c:493 [inline]
 vfs_read+0x82e/0xb40 fs/read_write.c:574
 ksys_read+0x12a/0x250 fs/read_write.c:716
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x119/0x710 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f85ccf47407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fffa6143830 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f85cce59880 RCX: 00007f85ccf47407
RDX: 0000000000001000 RSI: 000056446cb63580 RDI: 000000000000000c
RBP: 00007f85cd08fff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007f85cd08fea0 R14: 0000000000000000 R15: 000056446cb19090
 </TASK>

Allocated by task 11:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5414 [inline]
 __kmalloc_noprof+0x315/0x7e0 mm/slub.c:5439
 _kmalloc_noprof include/linux/slab.h:995 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 snd_card_new+0x74/0x110 sound/core/init.c:184
 create_card sound/usb/caiaq/device.c:429 [inline]
 snd_probe+0x209/0x1270 sound/usb/caiaq/device.c:544
 usb_probe_interface+0x386/0x9b0 drivers/usb/core/driver.c:399
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3776
 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3776
 usb_new_device.part.0+0xcc2/0x1686 drivers/usb/core/hub.c:2708
 usb_new_device drivers/usb/core/hub.c:5833 [inline]
 hub_port_connect drivers/usb/core/hub.c:5580 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5720 [inline]
 port_event drivers/usb/core/hub.c:5884 [inline]
 hub_event.cold+0x51a/0xe9d drivers/usb/core/hub.c:5966
 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
 process_scheduled_works kernel/workqueue.c:3479 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x69f/0xc90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 11:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x43/0x70 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2748 [inline]
 slab_free mm/slub.c:6499 [inline]
 kfree+0x20c/0x650 mm/slub.c:6792
 snd_card_do_free sound/core/init.c:609 [inline]
 release_card_device+0x1d4/0x230 sound/core/init.c:153
 device_release+0xd2/0x270 drivers/base/core.c:2640
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1f7/0x640 lib/kobject.c:737
 put_device+0x1f/0x30 drivers/base/core.c:3884
 snd_card_free_when_closed sound/core/init.c:630 [inline]
 snd_card_free_when_closed sound/core/init.c:624 [inline]
 snd_card_free+0x11a/0x190 sound/core/init.c:662
 snd_probe+0xdc3/0x1270 sound/usb/caiaq/device.c:553
 usb_probe_interface+0x386/0x9b0 drivers/usb/core/driver.c:399
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3776
 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3776
 usb_new_device.part.0+0xcc2/0x1686 drivers/usb/core/hub.c:2708
 usb_new_device drivers/usb/core/hub.c:5833 [inline]
 hub_port_connect drivers/usb/core/hub.c:5580 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5720 [inline]
 port_event drivers/usb/core/hub.c:5884 [inline]
 hub_event.cold+0x51a/0xe9d drivers/usb/core/hub.c:5966
 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
 process_scheduled_works kernel/workqueue.c:3479 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x69f/0xc90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff888109fec000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 4499 bytes inside of
 freed 8192-byte region [ffff888109fec000, ffff888109fee000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x109fe8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff888100042280 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 0200000000000040 ffff888100042280 dead000000000100 dead000000000122
head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 0200000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1128, tgid 1128 (kworker/0:2), ts 609309106561
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0xf4b/0x3440 mm/page_alloc.c:3943
 __alloc_frozen_pages_noprof+0x2d7/0x2f70 mm/page_alloc.c:5436
 alloc_slab_page mm/slub.c:3347 [inline]
 allocate_slab mm/slub.c:3462 [inline]
 new_slab+0xa9/0x6e0 mm/slub.c:3513
 refill_objects+0xe3/0x410 mm/slub.c:7410
 refill_sheaf mm/slub.c:2885 [inline]
 __pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
 alloc_from_pcs mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:4984 [inline]
 __do_kmalloc_node mm/slub.c:5413 [inline]
 __kmalloc_noprof+0x61c/0x7e0 mm/slub.c:5439
 _kmalloc_noprof include/linux/slab.h:995 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 __devm_drm_dev_alloc+0x2a/0xf0 drivers/gpu/drm/drm_drv.c:838
 gud_probe+0x407/0x1c50 drivers/gpu/drm/gud/gud_drv.c:469
 usb_probe_interface+0x386/0x9b0 drivers/usb/core/driver.c:399
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
page last free pid 2963 tgid 2963 ts 608596425768 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0x714/0xfc0 mm/page_alloc.c:2962
 __folio_put+0x278/0x470 mm/folio.c:105
 folio_put include/linux/mm.h:2160 [inline]
 put_page include/linux/mm.h:2229 [inline]
 put_netmem include/net/netmem.h:394 [inline]
 skb_page_unref include/linux/skbuff_ref.h:43 [inline]
 __skb_frag_unref include/linux/skbuff_ref.h:56 [inline]
 skb_release_data+0x649/0x8e0 net/core/skbuff.c:1116
 skb_release_all net/core/skbuff.c:1197 [inline]
 __kfree_skb+0x4f/0x70 net/core/skbuff.c:1211
 tcp_wmem_free_skb include/net/tcp.h:334 [inline]
 tcp_rtx_queue_unlink_and_free include/net/tcp.h:2325 [inline]
 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3698 [inline]
 tcp_ack+0x1f96/0x7420 net/ipv4/tcp_input.c:4400
 tcp_rcv_established+0x116d/0x3990 net/ipv4/tcp_input.c:6589
 tcp_v4_do_rcv+0x5bb/0xc30 net/ipv4/tcp_ipv4.c:1854
 tcp_v4_rcv+0x2e1a/0x4190 net/ipv4/tcp_ipv4.c:2248
 ip_protocol_deliver_rcu+0xba/0x4d0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x3f2/0x6e0 net/ipv4/ip_input.c:241
 NF_HOOK include/linux/netfilter.h:325 [inline]
 NF_HOOK include/linux/netfilter.h:319 [inline]
 ip_local_deliver+0x19d/0x570 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:480 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:623 [inline]
 ip_list_rcv_finish+0x946/0xbe0 net/ipv4/ip_input.c:675
 ip_sublist_rcv net/ipv4/ip_input.c:683 [inline]
 ip_list_rcv+0x338/0x450 net/ipv4/ip_input.c:717
 __netif_receive_skb_list_ptype net/core/dev.c:6307 [inline]
 __netif_receive_skb_list_core+0x74c/0x940 net/core/dev.c:6354
 __netif_receive_skb_list net/core/dev.c:6406 [inline]
 netif_receive_skb_list_internal+0x722/0xd40 net/core/dev.c:6497
 gro_normal_list include/net/gro.h:523 [inline]
 gro_normal_list include/net/gro.h:519 [inline]
 gro_flush_normal include/net/gro.h:531 [inline]
 napi_complete_done+0x221/0x940 net/core/dev.c:6865

Memory state around the buggy address:
 ffff888109fed080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888109fed100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888109fed180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff888109fed200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888109fed280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================